Device comprising a sound signal generator and method for forming a call signal

ABSTRACT

This device ( 1 ) enables the user to personalize the call signal (ringing) which it is called on to deliver. This personalization consists of transforming a melody (FIG.  1 ) which the user hums into his microphone in order to transform it into a polyphonic melody (FIG.  8 ). Application: Ringing for mobile telephones.

[0001] The invention relates to a device comprising a sound signalgenerator having an input element and a sound reconstruction element.

[0002] The invention also relates to a method for forming a call signal.

[0003] The invention finds important applications in particular withregard to the case where the sound signal, replacing traditionalringing, is the call signal for mobile telephones.

[0004] Such a device is known from European patent document EP 1 073034.In this known device, the sound signal can have a multitude of tones.However, it is considered that it does not leave enough initiative tothe user on the choice of ringing or call melodies.

[0005] The present invention proposes a device of the type mentioned inthe preamble which gives great initiative with regard to the productionof this call signal.

[0006] For this purpose, such a device is characterized in that it isprovided with a harmonization element for transforming, into apolyphonic melody formed from accompaniment notes, a monodic melodyentered by means of said input element, and a connection element forapplying said polyphonic melody to the sound reconstruction element.

[0007] A method for forming a call signal is characterized in that itcomprises the following steps:

[0008] entering a monodic melody formed from notes,

[0009] allocating a chord for the majority of these notes with a view toforming a polyphonic melody,

[0010] recording this polyphonic melody,

[0011] applying this polyphonic melody to a sound reconstruction elementin order to make a call.

[0012] The invention will be further described with reference toexamples of embodiment shown in the drawings to which, however, theinvention is not restricted. In the drawings:

[0013]FIG. 1 shows a device according to the invention.

[0014]FIG. 2 shows a monodic melody to be transformed according to theinvention.

[0015]FIG. 3 shows a first operation flow chart of the device of theinvention.

[0016]FIG. 4 shows a second operation flow chart of the device of theinvention.

[0017]FIG. 5 shows the states relating to chords allocated to thedegrees of a scale.

[0018]FIG. 6 shows a second embodiment of the invention.

[0019]FIG. 7 is a table intended to allocate values for each statetransition.

[0020]FIG. 8 shows the polyphonic melody obtained by the measures of theinvention.

[0021]FIG. 9 shows an operation flow chart for determining the key of amelody.

[0022] In FIG. 1, the device of the invention bears the reference 1.This device, in the context of the example described, is a mobiletelephone for a cellular network. This device has a transceiver part 5for transmitting and receiving waves by means of an antenna 7, a screen11, a keypad 10 and also an audio frequency circuit 15 for processingthe audio signals which come from a microphone 17 and the signals to beapplied to a loudspeaker 20. All the processings are implemented on thisdevice under the control of a processor assembly 30 cooperating with amemory assembly 35 containing, amongst other things, the instructionsfor these processings. The various items of information supplied andaccepted by these various elements pass over a common data line BUSAD.

[0023] When the user receives an incoming call which concerns him, theloudspeaker 20 emits a call signal, which the user would wish to be aspleasant as possible or which most seems to him to reflect hispersonality.

[0024] For this purpose, the invention proposes that the user himselfshould determine the call melody by singing or whistling into themicrophone 17. To make the melody more attractive, the device comprisesmeans for forming an accompaniment to this melody.

[0025]FIG. 2 shows a so-called monodic melody which the user has hummedinto his microphone 20. From this monodic melody, an accompaniment willbe established using the following operations performed by means inparticular of the processor 30 cooperating with the memory assembly 35.

[0026]FIG. 3 shows a flow chart intended for explaining the functioningof the invention. The box K1 indicates the melody entry step obtained bymeans, for example, of the microphone 17. Each of the notes entered isanalyzed and the frequency of these notes is determined (box K3). At thestep indicated by the box K5, it is examined whether the spacing of thenotes entered are multiples of the intervals of the tempered scale(¹²{square root}{square root over (2)}). The notes close to thesetempered levels are allocated to an accompanying chord, those too faraway are not. The close notes are allocated a flag Tp; this is indicatedin box K5. The box K7 indicates the establishment of each of the chordsfor the notes “Tp” according to a process detailed in FIG. 4. In boxK10, which can be an optional step, ornamental notes are added betweentwo successive chords. These ornamental notes are added when two notesin the melody are separated by a third. For example, if the two notes ofthe melody are doh and me, the ornament will be re. The step indicatedin box K12 is a step of recording the melody made polyphonic in thememory assembly 35.

[0027]FIG. 4 details the process set out in box K7. A processing stepconsists of finding the tonality of the monodic melody. The last note ofthe melody may define this (box K20). Then each note is allocated withthe degrees of the tonality (box K21), that is to say:

[0028] Tonic

[0029] Supertonic

[0030] Mediant

[0031] Subdominant

[0032] Dominant

[0033] Submediant

[0034] Leading note

[0035] For each of these degrees there are several possible predefinedchords (box K22). Referring to FIG. 5, two chords corresponding tostates S1 and S2 have been allocated. For the first degree (tonic) forexample, possible chords are doh-me-soh and soh-doh-me, considering thedoh major tonality. In these different states, there are also allocated“p” values of coefficients indicated in bold in the states which appearin the example of a monodic melody shown in FIG. 2. FIG. 6 also gives“p” values of transitions between chords. These values are also givenfor this same example of a melody.

[0036]FIG. 7 shows the possible paths for producing the accompanimentwith a view to supplying a polyphonic melody. The path is chosen whichgives the highest p value sum, and therefore state S1, state S3, stateS10 and state S1, the sum of the p values:

Σp=0.7+0.2+1+0.1+0.2+0.3+0.7=3.2

[0037] This value is the largest considering all the possible paths. Theoptimum path is chosen by using a Viterbi algorithm for example (boxK25, FIG. 4).

[0038]FIG. 8 shows the polyphonic melody thus obtained.

[0039] The melody thus recorded is available in order to be applied tothe loudspeaker 20. A connection between the memory 35 where it isrecorded will be established with the audio frequency circuit 15, viathe line BUSAD, so that the call signal can ring.

[0040]FIG. 9 shows a flow chart defining a variant of box K20 fordefining the tonality. It is based on the following considerations.

[0041] First of all a histogram of the notes of the melody isestablished (box K50). That is to say there is a statistic of the numberof dohs (N^(o)(doh)), doh# N^(o)(doh#) etc. It is also possible todefine a histogram vector of the notes of the melody for each level.That is to say, for H(doh), for example from the histogram (box K52)

[0042] H(doh)=[N^(o)(doh), N^(o)(doh#), N^(o)(re), N^(o)(re#),N^(o)(me), N^(o)(fah), N^(o)(fah#), N^(o)(soh), N^(o)(soh#), N^(o)(lah),N^(o)(lah#), N^(o)(te)]

[0043] H(doh#)=[N^(o)(doh#), . . .

[0044] etc.

[0045] where N^(o)(x) designates the number of “x” notes contained inthe melody.

[0046] The “pillar” notes of the tonality are levels 1, 4 and 5 (tonic,subdominant, dominant).

[0047] Levels 2, 3, 6 and 7 are rather less frequent, particularly withsimple melodies, which a normal user could enter.

[0048] Because of this, two “mask” vectors are defined, one in a majorand one in a minor. This mask weights the histogram of the notes of themelody.

[0049] For the major mask, it is possible to take the vector

[0050] AM=[5; 0; 2; 0; 3; 4; 0; 5; 0; 2; 0; 1].

[0051] For the minor mask:

[0052] Am=[5; 0; 2; 3; 0; 4; 0; 5; 2; 0; 1; 1].

[0053] It is also possible to define masks other than the major andminor modes.

[0054] Next, a “likelihood score” is calculated for the Doh Major andDoh minor tonality

[0055] true(DohM) AM*H(doh)

[0056] true (Dohm) Am*H(doh) where the symbol * designates the scalarproduct.

[0057] Next, the “likelihood score” is calculated for the 22 otherpossible tonalities.

[0058] (11 majors from doh#Major to te Major+11 minors from doh#minor tote minor)

[0059] by a simple translation of the values of the histogram (boxK(54)).

[0060] For example H(re)=[N^(o)(re), N^(o)(re#), N^(o)(me), N^(o)(fah),N^(o)(fah#), N^(o)(soh), N^(o)(soh#), N^(o)(lah), N^(o)(lah#),N^(o)(te), N^(o)(doh), N^(o)(doh#),] and

[0061] true(ReM)=AM*H(Re)

[0062] true(Rem)=Am*H(Re)

[0063] The final choice of the tonality is a function of the true( )values obtained.

[0064] By way of example, the tonality can be taken which maximizestrue( ) (box K56).

[0065] It should be noted that the melody can also be entered using thekeypad 10 of the device, keys being allocated to musical notes.

1. A device comprising a sound signal generator, having an input elementand a sound reconstruction element, characterized in that it is providedwith a harmonization element for transforming, into a polyphonic melodyformed from accompaniment notes, a monodic melody entered by means ofsaid input element, and a connection element for applying saidpolyphonic melody to the sound reconstruction element.
 2. A device asclaimed in claim 1, characterized in that the input element is amicrophone cooperating with a sound analyzer in order to supply scalenotes of said melody.
 3. A device as claimed in claim 2, characterizedin that the harmonization element comprises a chord library for eachscale level and a choosing element for determining the chord to beapplied to each note of said melody.
 4. A device as claimed in claim 2or 3, characterized in that the choosing element has means foroptimizing a harmony circuit from coefficients supplied to each of thechords and to the transitions between each chord.
 5. A device as claimedin claim 2 or 3 or 4, characterized in that the harmonization elementhas means of adding additional accompaniment notes.
 6. A device asclaimed in claim 2 or 3 or 4 or 5, characterized in that theharmonization element has selection means for determining the wrongnotes from the correct notes to which the chords will be allocated.
 7. Amethod for generating sound signals in a device as claimed in one ofclaims 1 to 6, characterized in that it comprises the following steps:entering a monodic melody formed from notes allocating a chord for themajority of these notes with a view to forming a polyphonic melodyrecording this polyphonic melody applying this polyphonic melody to asound reconstruction element for making a call.
 8. A method as claimedin claim 7, characterized in that it comprises the following steps fordetermining the tonality of the monodic melody: creating initial maskvectors for the major and minor tonalities or others histogram of allthe notes creating a vector for each degree of the scales scalar productof the vectors of degrees and the mask vectors allocating the tonalityaccording to the maximum values of this scalar product.